Marsbugs: The Electronic Astrobiology NewsletterVolume 11, Number 25, 16 June 2004

Editor/Publisher: David J. Thomas, Ph.D., Science Division, Lyon College, Batesville, Arkansas 72503-2317, USA. dthomas@lyon.edu

Marsbugs is published on a weekly to monthly basis as warranted by the number of articles and announcements. Copyright of this compilation exists with the editor, except for specific articles, in which instance copyright exists with the author/authors. Opinions expressed in this newsletter are those of the authors, and are not necessarily endorsed by the editor or by Lyon College. E-mail subscriptions are free, and may be obtained by contacting the editor. Information concerning the scope of this newsletter, subscription formats and availability of back-issues is available at http://www.lyon.edu/projects/marsbugs. The editor does not condone "spamming" of subscribers. Readers would appreciate it if others would not send unsolicited e-mail using the Marsbugs mailing lists. Persons who have information that may be of interest to subscribers of Marsbugs should send that information to the editor.

Articles and News

Page 1 CHEMISTS RETRIEVE CLUES TO ANCIENT OCEAN CHEMISTRY AND GLOBAL GREENHOUSE FROM CRETACEOUS SEDIMENTSUniversity of California, San Diego release

Page 2 MOON-TO-MARS COMMISSION RECOMMENDS MAJOR CHANGES AT NASABy Brian Berger

Page 3 DR. DOOLITTLE IN THE DOGHOUSEBased on a Science report

Page 3 GREAT TERRAFORMING DEBATE, PART I: GIVING MARS BACK ITS HEARTBEATFrom Astrobiology Magazine

Page 5 NASA DEVICE MONITORS HEALTH OF SCIENTISTS AND EXPLORERSNASA/ARC release 2004-191

Page 5 GREAT TERRAFORMING DEBATE, PART II: LOOKING FOR MARTIAN LIFEFrom Astrobiology Magazine

Page 7 NASA ADMINISTRATOR SHARES APPRECIATION FOR PRESIDENTIAL COMMISSION NASA release 2004-195

Page 7 GREAT TERRAFORMING DEBATE, PART III: SHOULD WE TERRAFORM?From Astrobiology Magazine

Page 8 DID COMETS FLOOD EARTH’S OCEANS?ESA release

Announcements

Page 9 NEW ADDITIONS TO THE ASTROBIOLOGY INDEXBy David J. Thomas

Mission Reports

Page 9 CASSINI UPDATESNASA/JPL releases

Page 13 MARS ROVERS GOING THE EXTRA MILENASA/JPL release 2004-151

Page 14 MARS EXPRESS: EVIDENCE OF FLOODING AT MANGALA VALLESESA release

Page 15 MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS release

Page 15 MARS ODYSSEY THEMIS IMAGESNASA/JPL/ASU release

Page 15 ROSETTA: CRUISE PHASE BEGINSESA release

CHEMISTS RETRIEVE CLUES TO ANCIENT OCEAN CHEMISTRY AND GLOBAL GREENHOUSE FROM CRETACEOUS SEDIMENTSUniversity of California, San Diego release

10 June 2004

Global warming, rising sea levels, massive volcanic activity around the world, widespread erosion—it's not a scene from the latest Hollywood disaster film, The Day After Tomorrow, but the Earth as it appeared during the mid- to late-Cretaceous geological period, 135 million to 65 million years ago, when the largest dinosaurs ruled the planet. Scientists have long sought clues to the Earth's ancient climate from ice cores that go back hundreds of thousands of years. Now, chemists at the University of California, San Diego and Stanford University report in the June 11 issue of Science that they have extended their glimpse of Earth's oceanic and atmospheric past to 130 million years, during one of its greatest upheavals of climatic change. Their results, the first high-resolution record of changes in seawater sulfate, provide a portrait of the interactions between the Earth and its atmosphere during the Cretaceous that should help scientists improve their predictions of how our climate might change as the accumulation of carbon dioxide and other greenhouse gases from human activities warm the planet.

An Ocean Drilling Program ship. Image credit: Texas A&M University.

Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 25, 16 June 2004

"The planet during the Cretaceous was very different than it is today," says Adina Paytan, an assistant professor of geological and environmental sciences at Stanford and the first author of the paper. "Not only were dinosaurs present, but the climate was extremely warm and global sea levels were significantly higher than they are today. Understanding how the atmosphere, land and ocean system interacted while in this global greenhouse mode is very relevant if we want to understand the fate of our future climate."

"This was a time when there were no glaciers in either the Arctic or Antarctic," says Miriam Kastner, a professor of earth sciences at UCSD's Scripps Institution of Oceanography and a co-principal investigator of the study. "So the record that we have obtained is an unusual portrait of an extreme climate in the Earth's past that will help us develop better predictive models in the future."

"If we can explain the major excursions that occurred 100 million years ago, we can develop good models of what is going to happen in the future," says Mark H. Thiemens, dean of UCSD's Division of Physical Sciences and a co-author of the paper. "This was a period of extremes."

The scientists obtained their high-resolution record of climatic changes during the Cretaceous from sulfur deposited over millions of years in ocean sediments in the mineral barite and retrieved from deep ocean cores. Sulfur in its various chemical forms can provide an uninterrupted record of large scale geochemical processes on the Earth's land masses and its oceans, as well as an indirect measure of its atmosphere.

Workers retrieve a deep sea sediment core. Image credit: Texas A&M University.

For example, variations in the four most common isotopes, or forms, of sulfur incorporated into sulfide and sulfate minerals give an indirect measure of how much oxygen was present in the atmosphere at the time. Continental weathering, geothermal activity and volcanism have other distinct sulfur isotope signatures, allowing the scientists to infer at specific points in the Earth's history what processes dominated the land masses and how they might have affected the atmosphere and climate. Because much of these chemicals eventually made their way to the oceans, the seawater sulfur deposited in ocean floor sediments has proven to be a particularly good way to glimpse geological and atmospheric changes over periods of millions of years.

"The sulfur isotopes provide an insight into carbon cycling in the oceans that includes fluctuations in productivity or organic matter burial," says Kastner. "The intimate coupling between the global biogeochemical cycles of sulfur and carbon constitutes a major control on the level of atmospheric oxygen. Therefore, the study of these cycles and how they have varied with time is important for the history of Earth's environment."

Kastner, Thiemens and Paytan, a former graduate student and postdoctoral fellow in Kastner's laboratory, discovered from their sulfur record that much less sulfur-34 isotope was deposited during the Cretaceous than in the previous 45 million year period of the Earth's history, "most likely as a result of extensive volcanic activity," they write in their paper.

The scientists found that from 120 million years ago to 105 million years ago, then again from 95 million years ago to 80 million years ago, the fraction of sulfur-34 dipped even more precipitously, suggesting a sharp reduction in the amount of organic matter buried in the ocean and used by sulfate-reducing bacteria. These changes in the productivity of ocean life suggest that the Earth's atmosphere may have gone through fluctuations in the amount of available oxygen, the scientists conclude in their paper.

"One thing that we can learn from this record is that there might have been more rapid changes in the atmosphere of the Cretaceous than we knew about," says Paytan. "Some relatively rapid changes can happen on Earth. So we have to be prepared."

Douglas Campbell, an undergraduate student at UCSD working in Kastner's laboratory also contributed to the study. The research project was funded by the National Science Foundation, which also operates the Deep Sea Drilling Project and Ocean Drilling Program, which made available the sediment cores.

Contacts:Kim McDonald, UCSD media contactPhone: 858-534-7572E-mail: kmcdonald@ucsd.eduhttp://ucsdnews.ucsd.edu

Miriam Kastner, UCSDPhone: 858-534-2065E-mail: mkastner@ucsd.edu

Mark Thiemens, UCSDPhone: 858-534-6882E-mail: mthiemens@ucsd.edu

Adina Paytan, Stanford UniversityPhone: 650-724-4073E-mail: apaytan@pangea.stanford.edu

Read the original news release at http://ucsdnews.ucsd.edu/newsrel/science/mccretaceous.asp.

Read the Science article at http://www.sciencemag.org/cgi/content/abstract/304/5677/1663.

An additional article on this subject is available at http://www.spacedaily.com/news/early-earth-04i.html.

MOON-TO-MARS COMMISSION RECOMMENDS MAJOR CHANGES AT NASABy Brian BergerFrom Space.com

11 June 2004

A commission chartered by U.S. President George W. Bush to advise him on implementing a broad new space exploration vision is recommending streamlining the NASA bureaucracy, relying more heavily on the private sector, and maintaining more oversight of the nation’s space program at the White House. The President’s Commission on Implementation of U.S. Space Exploration Policy is scheduled to release its final report June 16. A copy of that report, “A Journey to Inspire, Innovate, and Discover”, was obtained by Space News. The 60-page report outlines the organizational changes the commission says NASA needs to make if it is to achieve the space exploration

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goals laid out by Bush in January. Those goals include returning humans to the moon by 2020 in preparation for eventual human expeditions to Mars.

Read the full article at http://www.space.com/news/commission_report_040610.html.

DR. DOOLITTLE IN THE DOGHOUSEBased on a Science report

11 June 2004

If we encountered another intelligent species on another planet, could we understand them? In turn, could extrasolar species decipher one of our eight-thousand terrestrial languages in use today? To better understand the deeper connection between language and intelligence—two key steps in improving the probabilities of contact with intelligent life elsewhere in the universe—the SETI Institute shepherds this relatively new field in astrobiology. For instance, Dr. Laurance Doyle of the SETI Institute works with biologists Brenda McCowan and Sean Hauser, of the University of California, Davis, studying non-human communication systems. Doyle's group, which also included Institute colleagues Dr. Christopher Chyba and Taylor Bucci, have already explored communication between sea mammals, like feeding humpback whales near Glacier Bay, Alaska.

If one considers the classic probabilities for such contact to succeed, the likelihood is governed by the Drake Equation, a formula for divining what might enable two different species to talk intelligently. One specific term in the Drake equation captures the probabilty that intelligence has evolved on another planet. But a pragmatic and implicit part of that probability hinges on whether humans and another species might be able to understand what the other one is trying to communicate. The problem poses a dilemma: can a species be considered intelligent yet unable to communicate its own wit to others?

Astronomer Guy Consolmagrio posed the scenario directly: "[It's possible] we find an intelligent civilization and there's no way in creation we can communicate with them because they're so alien to us. We can't talk to dolphins now. In which case, we'll never know."

Identifying examples of successful human to non-human communication offers few complete cases to study. Humans have considerable challenges just to understand each other, much less another species. The search for a good working example however may hold promise as a nascent discipline to bridge inter-species language barriers. One case to consider is a familiar one: does your dog understand what you say?

Dog owners convinced of their pets' grasp of human language may be validated, at least in part, by new research on the word-learning abilities of a German family's Border collie. Scientists who studied a dog with an approximately 200-word "vocabulary" suggest that some aspects of speech comprehension evolved earlier than, and independent from, human speech. This research appears in the 11 June 2004 issue of the journal, Science, published by AAAS, the nonprofit science society.

"You don't have to be able to talk to understand a lot," said senior Science author Julia Fischer from Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

Rico, the nearly nine-year-old Border collie, can learn the names of unfamiliar toys after just one exposure to the new word-toy combination. The scientists equate the dog's apparent learning to a process seen in human language acquisition called "fast mapping." The fast mapping abilities of children allow them to form quick and rough hypotheses about the meaning of a new word after a single exposure.

"Such fast, one-trial learning in dogs is remarkable. This ability suggests that the brain structures that support this kind of learning are not unique to humans, and may have formed the evolutionary basis of some of the advanced language abilities of humans," said Katrina Kelner, Science's deputy editor for life sciences.

The German team first verified Rico's 200-word "vocabulary." In a series of controlled experiments, Rico correctly retrieved, by name, a total of 37 out of 40 items randomly chosen from his toy collection. The authors write that Rico's "vocabulary size" is comparable to that of language-trained apes, dolphins, sea lions and parrots.

Next, the researchers tested Rico's ability to learn new words through fast mapping. Fischer's team placed a new toy among seven familiar toys. In a separate room, the owner asked Rico to fetch the new item, using a name the Border collie had never heard before. Rico correctly retrieved a new item in seven of ten sessions. He apparently appreciates, as young children do, that new words tend to refer to objects that do not already have names. After a month without access to these target toys, Rico retrieved them, upon request, from groups of four familiar and four completely novel toys in three out of six sessions. His retrieval rate is comparable to the performance of three-year-old toddlers, according to the authors.

"For psychologists, dogs may be the new chimpanzees," writes Paul Bloom from Yale University in New Haven, CT, in an accompanying "Perspective" article in Science. Scientists around the world are currently studying how chimpanzees learn language and communicate.

The authors do not claim that Rico and children have an equally rich understanding of words. They do show, however, that Rico can make the link between objects and sounds.

"This is a crucial step that allows an animal to figure things out in the environment," Fischer explained.

Fischer's team is now investigating Rico's ability to understand entire phrases, such as requests for Rico to put toys in boxes, or to bring them to certain people. Fischer noted that people should not take this study as a reason to go out and get a Border collie as a novelty.

"Border collies are working dogs," Fischer said. "If they were humans, we'd call them workaholics. They are high-maintenance, professional dogs that need at least four or five hours of attention a day."

Read the original article at http://www.astrobio.net/news/article1015.html.

Read the Science articles at:http://www.sciencemag.org/cgi/content/summary/304/5677/1605http://www.sciencemag.org/cgi/content/short/304/5677/1682

GREAT TERRAFORMING DEBATE, PART I: GIVING MARS BACK ITS HEARTBEATFrom Astrobiology Magazine

14 June 2004

At the Astrobiology Science Conference on March 30, scientists and science fiction writers faced off in front of a packed audience to debate the promise and pitfalls of terraforming Mars. In part 1 of this 7-part series, Christopher McKay advocates making Mars habitable for martians. The Mars Terraforming Debate is co-sponsored by NASA's Astrobiology Magazine, the SciFi Museum (Seattle), and Breakpoint Media.

Donna Shirley: The Red Planet is again making headlines. Rovers are now exploring the surface of Mars, making exciting discoveries about the planet's environmental history. Today's exploration will help researchers of the future design habitable environments on Mars.

Terraforming was once solely the province of science fiction. In the 1930s, Olaf Stapledon wrote of electrolyzing a global sea on Venus in order to prepare it for human habitation in Last and First Men. Jack Williamson coined the term "terraforming" in the 1940s in a series of short stories. And in 1951, Arthur C. Clarke gave the concept wide exposure with his novel, The Sands of Mars. Kim Stanley Robinson picked up the terraforming torch in the 1990s with his epic trilogy—Red Mars, Green Mars and Blue Mars.

Scientists began to think seriously about terraforming in the 1960s, when Carl Sagan published several articles dealing with the possibility of terraforming

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Rico, a dog with an approximately 200-word "vocabulary," can learn the names of unfamiliar toys after just one exposure to the new word-toy combination. Image credit: Susanne Baus.

Marsbugs: The Electronic Astrobiology Newsletter, Volume 11, Number 25, 16 June 2004

Venus. Terraforming Mars has been the major subject of research of two of our panelists tonight, Dr. Chris McKay and Dr. Jim Kasting, since the 1970s.

So the question is, can we terraform Mars? How would we do it, why would do it, when we do it, and should we do it?

Science Fiction Meets Science Fact. "What are the real possibilities, as well as the potential ramifications, of transforming Mars?" Terraform debaters left to right: Greg Bear, author of such books as Moving Mars and Darwin's Radio; David Grinspoon, planetary scientist at the Southwest Research Institute; James Kasting, geoscientist at Pennsylvania State University; Christopher McKay, planetary scientist at NASA Ames Research Center; Lisa Pratt, biogeochemist at Indiana University; Kim Stanley Robinson, author of the "Mars Trilogy" (Red Mars, Green Mars and Blue Mars); John Rummel, planetary protection officer for NASA; moderator Donna Shirley, former manager of NASA's Mars Exploration Program at the Jet Propulsion Laboratory.

Chris McKay: I don't think we can terraform Mars, if terraforming is, as it was originally defined, making Mars suitable for human beings. But what we could do is make Mars suitable for life. Human beings are a particular subset of life that require particular conditions. And it turns out oxygen in particular is very hard to make on Mars. That is, I think, beyond our technological horizons—it's a long time in the future. But warming Mars up, and restoring its thick carbon dioxide atmosphere, restoring its habitable state, is possible. It's sort of a stretch of the word terraforming, but if you want to call that terraforming, that's possible. Bob McElroy coined the phrase "ecosynthesis" for that, and I think that's a better word.

So I'll answer, "Yes! We can bring Mars back to life." How? Well, the biggest problem is warming it up. We know how to warm up planets, we're doing it on Earth. In fact the same sorts of things would work on Mars.

Should we do it? Well, that gets down to a question that we've never had to face on Earth before: the distinction between nature and life. On Earth there is no meaningful distinction between nature and life, even in the remotest, coldest deserts.

We see that distinction for the first time when we look beyond the Earth, when we look at the moon. There's nature; there's no life. When we look at Mars, we also see nature, probably no life. It's different from the moon, and we lack the word that distinguishes between something that's dead, and something that was never alive. The moon was never alive. Mars is dead. The question in my mind is—should we bring it back to life?

Well, I vote for life. Nature's a great thing. Mars lived fast, died young and left a beautiful body—the Sylvia Plath approach to planetary science. We could play Ted and just ignore it, or we could do something better and bring it back to life. Mars is beautiful the way it is, but I think it would be even better if we could restore the biosphere that it once had. So I vote for life.

I apologize that I'll have to leave in about 15 minutes—as it turns out I'm giving a lecture at a class on ethics at Stanford on the same topic, of terraforming Mars. Who would think it would be so popular that I'd have a conflict like this?

Donna Shirley: Lisa would you like to respond to that?

Lisa Pratt: I'm afraid I'm going to have to violently disagree. I think we have no reason whatsoever to think that Mars is dead or sterile or even hostile to life forms. I think it's increasingly evident that there is a large inventory of water on Mars. There may in fact be groundwater relatively close to the surface, meaning, within a few hundred meters of the surface. The kinds of chemistries that are suggested by the evaporite minerals indicate that the

groundwater may be a brine with a perfectly habitable composition. In fact, it may contain a soup of molecules that would be delicious for any number of Earthly microbes. So I think until we successfully interrogate the martian subsurface, and adequately address the possibility of indigenous martian organisms, that we absolutely should not think about terraforming Mars.

Donna Shirley: So Jim, if we did terraform Mars, how long would it take? What kinds of things could we do to make that happen?

James Kasting: Well, Chris has hit the nail on the head. Of course I was a co-author on the paper we wrote on that. In that Nature paper, we defined two levels of terraforming Mars: one was for humans and one was for plants. The one that seems potentially doable, although it's difficult by itself, is to do it for plants. To me, that's not that interesting. Co-authors can disagree on what the paper implies, and I personally wouldn't go to the trouble to terraform Mars just to make it habitable for plants. I'm more interested in humans.

But as Chris already pointed out, the oxygen is a major problem. If you think about oxygen in the Earth's present atmosphere, you have to bury organic carbon. It's not enough just to have photosynthesis, you have to bury the organic carbon that you've produced. On Earth, we bury about one-tenth of 1 percent of primary productivity in the oceans, and that gives oxygen about a 4 million-year lifetime, meaning you have to do that for 4 million years.

Now, if you're really optimistic, suppose you could get oceans going on Mars, and you had as much productivity as you had on the Earth. And let's say that instead of burying 0.1 percent you could figure out how to make that system bury 10 percent of the organic carbon. It would still take forty thousand years to build up oxygen. That's a daunting task which I hardly can envision us doing. So that leaves us with terraforming it for plants, and, well, we can debate whether that's worth doing or not.

Donna Shirley: So, Greg. If we only had terraforming to make things habitable for carbon dioxide breathers, as Chris suggests, would anyone be interested in doing it?

Greg Bear: That's an interesting question, but we have to look at our motivations for terraforming Mars. Is it because we want to transform Mars for the art of doing it, for the science of doing it, or for the economic necessity of doing it?

You know, at this point, it's kind of tough imagining doing that for any of these reasons, because it would take so darn long. And usually our economic basis of doing this sort of activity requires a two-year time span for delivery of goods, so unless we start thinking very far out, like the Japanese, but hyper-cubed, then we really have to think of, well, why would we want to get this started? To leave a legacy for the next species on the planet Earth? It's about how long it's going to take. And will we be around when it's done?

If we're going to do it for an experimental purpose, then we have to define the terms of the experiment. So, it's a huge question, and we just don't have the information about either ourselves or Mars to figure out the answer to it.

Donna Shirley: So John, what information do we need about Mars?

John Rummel: I think that we're talking about the trajectory for Mars, and not necessarily as some other kind of an opportunity. Mars in forty thousand years might be a wonderful place if we started now. The question is, we can't go back when we start with the wrong propositions.

The Earth a couple of billion years ago was not all that comfortable to humans. In fact, we had bacteria that were not really happy when other organisms showed up and started breaking water (molecules), and making oxygen, and releasing it into the atmosphere. As it's turned out, over time organisms have been able to modify this planet, not only in the atmosphere itself, but also all the way down into the mantle. Cyanobacteria are the culprits involved here; these are the organisms that caused the demise of the original inhabitants of this planet. They didn't worry about the time scale; they worried about their trajectory.

Forty thousand or fifty thousand years is the time span at which Mars terraforms itself. Mars is a place that may be terraforming on a regular basis. So get in now and avoid the rush. We need to know, before we go, whether or not, if we adopt a trajectory, are there martian organisms there? As we push Mars towards being more Earth-like, are there organisms there that will push back, that will do what we would consider to be socially unproductive things,

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like covering the planet with poisons? So let's think about whether or not Mars should be pushed in that direction. Once you make the decision, then I don't have a job anymore.

Donna Shirley: I'm going to give Chris the last word here since he has to leave. So anything else you want to say about terraforming Mars?

Chris McKay: I just want to add one more point about martian life. I think that we should make a biosphere on Mars, as I said earlier. I think the ingredients of the biosphere—the genome of that biosphere—if at all possible, should be martian. That would be the most interesting situation.

We have evidence that Mars had life—we have evidence it had water, from there we deduce that it had life. I think an objective assessment of the situation leads us to be very pessimistic that that life survived intact today. But for a variety of reasons I think we could find the relics of it—frozen and dead maybe—and reconstruct it if we had to, or find it living in some subsurface refuge, and let it once again control the biogeochemical cycles of that planet the way that life on Earth controls the biogeochemical cycles of our planet. In other words, give Mars back its heartbeat.

I'm not proposing to send life from Earth there. That's only the last resort. If Mars has no genome, then we could share ours with it. But I personally think that a Mars full of Martians is much more interesting than Mars full of Earthlings.

Read the original article at http://www.astrobio.net/news/article1017.html.

NASA DEVICE MONITORS HEALTH OF SCIENTISTS AND EXPLORERSNASA/ARC release 2004-191

15 June 2004

A lightweight, portable device developed by NASA scientists is enabling physicians to monitor the health and safety of explorers in remote locations on Earth. It may eventually be used in space to monitor astronauts during space travel. The wireless LifeGuard system watched over the vital signs of several expedition members who sampled soils and water from the world's highest alpine lake, nearly 20,000 feet up the Licancabur volcano, on the border between Chile and Bolivia, last year.

The LifeGuard monitoring system. Image credit: Stanford University.

"Having the team wearing these LifeGuard systems added an element of safety in this extreme environment," said expedition leader Nathalie Cabrol of NASA's Ames Research Center (ARC), Moffett Field, Calif. The system allows real-time monitoring of vital parameters such as heart rate, blood pressure, electrocardiogram (EKG), breathing rate, and temperature. It can also measure human movements in three dimensions. The LifeGuard units sent real-time vital signs from subjects at the volcano to scientists at ARC by satellite. This demonstrated the monitor's potential to work in an extreme environment. The test demonstrated the enhanced ability for doctors to practice telemedicine over long distances on Earth or potentially in space.

"More recently, we did experiments aboard NASA's KC-135 aircraft that flies big, rollercoaster-like maneuvers to create short periods of weightlessness," said Dr. Gregory Kovacs of Stanford University, Stanford, CA. "During the KC-135 flights, we explored the body's vital signs' response to changing gravitational forces, and we transmitted the wireless data from the subject to another location in the plane. The experiments were quite successful."

"The data logger part of the system that collects data from body sensors is about the size of your palm and weighs about 166 grams (six ounces)," said Carsten Mundt, an engineer who is developing LifeGuard at ARC. "The sensors we use are quite easy to apply and comfortable to wear," Mundt said.

The LifeGuard's button sensors stick to the skin to take EKG and breathing rate. The device uses an arm cuff to measure blood pressure. The data logger connects to a sensor clipped or wrapped on an index finger to measure oxygen in the blood and pulse rate. The system's sensors connect to the LifeGuard by wires. LifeGuard's data logger has a transmitter that radios collected data to a base station computer. The data logger has sensors that measure astronaut movements in three dimensions.

"LifeGuard also could be used by physicians on Earth, since the system could be put on a patient very quickly and transmit vital signs during transfer to the hospital," Mundt said. "When the patient comes in, the doctor would already know the status of the patient," Mundt added.

"The system can be worn by firefighters and hazardous material workers to monitor their health during activities," Mundt said. "It could even be worn by patients at home," he added. Home uses could include diagnosing sleep disorders, heart disease or unsteady gait in the elderly.

The NASA team working on the LifeGuard system has been developing physiological monitors for the past decade. The Astrobionics team at NASA began work on LifeGuard in October 2002, and is collaborating with the National Center for Space Biological Technologies at Stanford University. The research is in support of the NASA Office of Exploration Systems and the Vision for Space Exploration. For more information about LifeGuard on the Internet, visit http://LifeGuard.stanford.edu. For information about NASA and agency programs on the Internet, visit http://www.nasa.gov.

Contacts:Dolores BeasleyNASA Headquarters, Washington, DCPhone: 202-358-1753

John Bluck NASA Ames Research Center, Moffett Field, CAPhone: 650-604-5026

Rosanne SpectorStanford University Medical Center, Stanford, CAPhone: 650-725-5374

GREAT TERRAFORMING DEBATE, PART II: LOOKING FOR MARTIAN LIFEFrom Astrobiology Magazine

15 June 2004

At the Astrobiology Science Conference on March 30, scientists and science fiction writers faced off in front of a packed audience to debate the promise and pitfalls of terraforming Mars. In part 2 of this 7-part series, John Rummel predicts that in our search for life on Mars, we probably won't find cows. The Mars Terraforming Debate is co-sponsored by NASA's Astrobiology Magazine, the SciFi Museum (Seattle), and Breakpoint Media.

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Donna Shirley: David, making a planet habitable is something that people have said is maybe a good thing to do, maybe not a good thing to do. And the question is, since your research is on climate evolution and habitability, can we do it?

David Grinspoon: Can we do it? I think that, in the long run, we probably could if we wanted to, from a technical point of view. But my concern is not over the technical difficulty, but the societal problems. I think that human technical ability increases fast; it increases exponentially. Human wisdom increases much more slowly.

But, to my mind, I think that if a hundred years from now, we decided that we wanted to terraform Mars, we would know how to do it. We already have some ideas, and we're getting smarter all the time about how planetary climate works from a technical point of view.

But whether we have the other abilities that we need, in terms of the collective decision-making that it takes to purposefully transform a planet, right now we're having trouble purposely not transforming our own planet. We're having trouble not veneraforming the Earth, in a sense. And I think if we get to the point where we demonstrate that we have the wisdom to take care of Earth's climate, and not haphazardly, but in a collective way, where we decide that we're going to make these decisions and we're able to control Earth's climate, then maybe we will have the wisdom to terraform Mars.

We should be thinking about terraforming Mars. I don't think we should terraform Mars now, but as we think about it, we work the problem of how do we purposefully take care of a planetary climate. So I think that this exercise of considering terraforming Mars is very good for us, and is maybe a first step towards attaining the kind of wisdom that we need to someday be smart enough—not just technically, but also ethically and in terms of collective decision-making—to terraform Mars.

Donna Shirley: Stan, you've written about all those things. One of the things that you've written about is the role of Antarctica in preparing us to go to Mars. What would you say about the question of should we do it, and what should we do?

Kim Stanley Robinson: I think that Antarctica will serve as a good analog for Mars. (Mars) will be a distant place that's cold. There will be scientific stations there. And it'll be interesting to the rest of humanity, but somewhat remote. Scientists will be rotating crews coming back after their stay. And what we learn there will teach us more about taking care of the Earth. So, if you want to think about what Mars can be compared to in the rest of human history, because in many ways it's entirely a new thing, I think Antarctica is a much better model than the Wild West or any other model that's been proposed.

But this question of should we terraform or not, I find it really interesting because the scientists are still split on the question of whether we have any good expectation of finding indigenous life there. So it becomes a kind of decision-tree that we have to answer—like forks in paths, we have to come to a fork, find a way to make a decision, and then move on to the next decision.

The first question we need to answer is, is there life there right now alive, or not? When we answer that, and if the answer's in the negative, we can then proceed with essentially a dead rock that's very big and really interesting, and bringing life seems the obvious thing to do. A project which the industrial capacities of humanity may grow in ways that are as surprising to us as (our technology would be surprising to) the people in the 17th century.

If we do find life on Mars, it will be very interesting to try to discover whether it is indigenous, which is to say a second start, and truly alien to us, a second genesis. In that case, I think we'll have to go and try to kill all the bacteria that are already there, inside the boxes that we've left, and try to clean up and really study it from a distance. That will be a really remarkable discovery, perhaps the major discovery in human history.

But if we find that the life there has the same DNA, the same patterns, and is clearly bacteria that got bounced up there from Earth, or vice versa, and that we're all martian bacteria that got bounced down here and then evolved—if they're cousins, in a sense, then I think you could go on for a few centuries and begin to feel that we could move to Mars and live on Mars. The local cousins would have their niches, and we would have our niches, and then let the two begin to interpenetrate again.

At each point we need to make these decisions without being able to say right now, "Oh, we should terraform Mars," or, "Oh, we shouldn't terraform Mars." We can't answer that yet. But I agree that it is a completely useful thought experiment. Because it's really the terraforming of Earth that we are now doing, in ignorance and by accident. And so we need to know more about it.

Donna Shirley: Lisa, you found cave creatures way down below the Earth. Can they co-exist with the creatures on the surface? Seems like a Mars analog to me.

Lisa Pratt: I think certainly on Earth, as we begin to look at greater and greater depths and into increasingly extreme environments, we realize that we are co-habitating with organisms that live very much in partitioned ecosystems, where organisms from one cannot survive in the other. So, in that sense, one can perhaps imagine a situation where there would be indigenous martian organisms that continue to reside in the deep subsurface, relatively protected and isolated.

But I think the problem for us as a scientific community, and the problem for the public as a whole, is that until we know enough about the subsurface of Mars to make an informed decision, it's really difficult to move forward. Right now, we barely know enough about the subsurface of Earth to make informed decisions. We're discovering, practically on a daily basis, organisms in places that we, as recently as 10 years ago, were absolutely certain were barren of life.

As we have begun to get samples back that are clean enough of surface contamination to think that we're actually looking at deep subsurface materials, what we realize is we know the organisms are there because we can identify their genes, but we can't culture most of these organisms. So we don't in fact know what their requirements for life are. In some cases, we know what their energy source is. In some cases we know what their carbon source is. But the vast majority of microbial organisms remain unculturable, even on planet Earth.

Donna Shirley: John, if subsurface microbes are unculturable, how do you know when there is life there or not? How do we know when we can safely assume Mars is dead and start terraforming?

John Rummel: Well, the good news is that life, when it's there, tends to leave little dead life around. So you can pick out the dead bug bodies. They play hell with organic chemistry, and that's a good thing. But they also change the environment around them. Basically, you're moving material and energy around, back and forth, to attain some particular end, usually the result is more microbes of one kind or another. And even if we can't grow them, it doesn't mean that they can't grow.

Our attempts to culture microbes are a little bit like trying to grow large mountain lions by feeding them wheat. It doesn't work very well, and it really ticks them off. I understand mountain bikers are a better diet, but that's a California joke.

I really think that eventually we will find out whether or not there is something there by their action on their own environment. But it will be critical to know these things before we attempt to modify the martian environment at all. And I think if we watch Mars for just a little bit while longer, even if there's nothing alive there, there are things going on. And those things may or may not lead you to a deduction that life is there.

We have people now reporting methane in the atmosphere. This is a detection from the planetary Fourier spectrometer. ESA, the European Space Agency, has put out an announcement that it's been detected at 10 to 20 parts per billion. Well, methane in the atmosphere on Mars can mean one of three things: either vulcanism, possibly microbial life, or maybe cows. We haven't seen the cows yet. I doubt that we'll find them. But one of the other two would be a very interesting thing to find out.

Whether or not we can find more methane on one part of Mars than another is going to take either more measurements from abroad or an instrument in situ, perhaps in orbit around Mars, that can really make high-definition measurements. So these are things for people to propose for future Scout opportunities or future Discovery opportunities to really nail it down. Then we'll have to go to those places and find out what's going on there. When we do, we don't want to take our own bacteria there so that they do those things themselves. We want to find out about Mars life before we take Earth life to a place where it can be modifying the environment in a way that we can't

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control. We're not trying to control Mars and martian life right now. If we ever want to, we want to make sure we don't screw it up first.

Read the original article at http://www.astrobio.net/news/article1018.html.

NASA ADMINISTRATOR SHARES APPRECIATION FOR PRESIDENTIAL COMMISSION NASA release 2004-195

16 June 2004

The following is a statement from NASA Administrator Sean O'Keefe regarding today's report from the President's Commission on Implementation of U.S. Space Exploration Policy.

"I want to express my sincere appreciation to chairman Pete Aldridge and the commissioners for their thoughtful efforts and dedication in developing recommendations for advancing our nation's new Vision for Space Exploration.

"In January, President George W. Bush charted a bold, new course for the future. In his historic address, the President charged us to open new frontiers, seek new discoveries and prepare for new journeys to worlds beyond our own.

"The recommendations released today by the commission will influence our work for years to come and will help guide us through a transformation of NASA. The specific details of this transformation will be announced in the days and weeks ahead and will be reflected by foundational changes in our organization and the way we do business.

"Transformation is essential if we're going to position ourselves to meet the requirements of this initiative. In the end, we'll be in a better position to expand human knowledge, revolutionize our understanding of the Universe and produce the technological advances that benefit everyone on Earth. The investments made in exploration lead to innovations that make our industrial and personal technology safer, faster, more affordable, more effective and easier to use.

"The commission's recommendations for this nation's new Vision for Space Exploration will help propel us into a prosperous, secure and bright future.

"While we have indeed accomplished a great deal in NASA's 45-year history, in many ways we are at the beginning of the age of space exploration. We now have the foundation on which NASA can build a vibrant, safe and sustainable journey."

To review the report on the Internet, visit http://www.nasa.gov/newvision.

Contact:Glenn Mahone/Bob JacobsNASA Headquarters, Washington, DC Phone: 202-358-1898/1600

GREAT TERRAFORMING DEBATE, PART III: SHOULD WE TERRAFORM?From Astrobiology Magazine

16 June 2004

At the Astrobiology Science Conference on March 30, scientists and science fiction writers faced off in front of a packed audience to debate the promise and pitfalls of terraforming Mars. In part 3 of this 7-part series, David Grinspoon says we have an ethical imperative to bring a dead planet to life. The Mars Terraforming Debate is co-sponsored by NASA's Astrobiology Magazine, the SciFi Museum (Seattle), and Breakpoint Media.

Donna Shirley: Greg, what are the ethics of exploring Mars?

Greg Bear: You usually talk about ethics within your own social group. And if you define someone as being outside your social group, they're also outside your ethical system, and that's what's caused so much trauma, as we seem to be unable to recognize people who look an awful lot like us as being human beings.

When we go to Mars, we're actually dealing with a problem that's outside the realm of ethics and more in the realm of enlightened self-interest. We have a number of reasons for preserving Mars as it is. If there's life there, it's evolved over the last several billion years, it's got incredible solutions to incredible problems. If we just go there and willy-nilly ramp it up or tamp it down or try to remold it somehow, we're going to lose that information. So that's not to our best interest.

We were talking earlier about having a pharmaceutical expedition to Mars, not just that but a chemical expedition to Mars, people coming and looking for solutions to incredible problems that could occur here on Earth and finding them on Mars. That could generate income unforeseen.

If we talk about ethical issues on a larger scale of how are other beings in the universe going to regard how we treat Mars, that's a question for Arthur C. Clarke to answer, I think. That's been more his purview: the large, sometimes sympathetic eye staring at us and judging what we do.

We really have to look within our own goals and our own heart here. And that means we have to stick within our social group, which at this point includes the entire planet. If we decide that Mars is, in a sense, a fellow being, that the life on Mars, if we discover them—and I think that we will discover that Mars is alive—is worthy of protection, then we have to deal with our own variations in ethical judgment.

The question is, if it's an economic reality that Mars is extraordinarily valuable, will we do what we did in North America and Africa and South America and just go there and wreak havoc? And we have to control our baser interests, which is, as many of us have found out recently, very hard to do in this country. So we have a lot of problems to deal with here, internal problems. Because not everyone will agree on an ethical decision and that's the real problem with making ethical decisions.

Donna Shirley: David, you want to comment on the ethics of terraforming Mars?

David Grinspoon: Well, one comment I've heard about recently, partly in response to the fact that the president has recently proposed new human missions to Mars—of course, that's not terraforming, but it is human activities on Mars—and I've heard a lot of people say, "Why should we go to Mars, because look at what human beings have done to Earth. Look at how badly we're screwing it up. Look at the human role on Earth. Why should we take our presence and go screw up other places?"

It's an interesting question, and it causes me to think about the ethics of the human role elsewhere. What are we doing in the solar system, what should we be doing? But, it's very hard for me to give up on the idea. Maybe because I read too much science fiction when I was a kid, I do have, I have to admit, this utopian view of a long-term human future in space. I think that if we find life on Mars, the ethical question's going to be much more complicated. But in my view, I think we're going to find that Mars does not have life. We may have fossils there. I think it's the best place in the solar system to find fossils. Of course, I could be wrong about this and I'd love to be wrong about it, and that's why we need to explore. If the methane observation is borne out, it would be, to me, the first sign that I really have to rethink this, that maybe there is something living there under the ice.

But let's assume for a second that Mars really is dead, and we've explored Mars very carefully—and this is not a determination we'll be able to make without a lot more exploration—but assuming it was, then what about this question. Should human beings go to Mars, because do we deserve to, given what we've done to Earth? And to me, the analogy is of a vacant lot versus planting a garden. If Mars is really dead, then to me it's like a vacant lot, where we have the opportunity to plant a garden. I think, in the long run, that we should.

We've heard a lot different possible motivations, economic motivations, or curiosity, but I think ultimately the motivation should be out of love for life, and wanting there to be more life where there's only death and desolation. And so I think that ethically, in the long run, if we really learn enough to say that Mars is dead, then the ethical imperative is to spread life and bring a dead world to life.

Donna Shirley: Jim, we can't prove a negative, so how do we know if there's life or not, if we keep looking and looking and looking. How long should we look? How would we make that decision?

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"I've heard a lot of people say, 'Why should we go to Mars, because look at what human beings have done to Earth." —David Grinspoon. Image credit: NASA.

James Kasting: I think Lisa put us on the right track initially. She's studying subsurface life on Earth. If there's life on Mars today, it's subsurface. I think it's deep subsurface, a kilometer or two down. So I think we do need humans on Mars, because we need them up there building big drilling rigs to drill down kilometers depth and do the type of exploration that Lisa and her group is doing on Earth here. I think that's going to take not just decades, but probably a couple of centuries before we can really get a good feel for that.

Donna Shirley: Well, I know, John, at Lake Vostok, one of the big issues is, if we drill into it, our dirty drilling rigs are going to contaminate whatever's down there. So how do we drill without worrying about contaminating something if it is there?

Lake Vostok, Antarctica. Image credit: NASA.

John Rummel: Well, you accept a little contamination probabilistically that you can allow operations and still try to prevent it. I mean, basically what we can do is try to prevent that which we don't want to have happen. We can't ever have a guarantee. The easiest way to prevent the contamination of Mars is to stay here in this room. Or someplace close by.

Greg Bear: That's known as abstinence.

John Rummel: [laughs]. I also want to point out it's not necessarily the case that the first thing you want to do on Mars, even if there's no life, is to change it. We don't know the advantages of the martian environment. It's a little bit like the people who go to Arizona for their allergies and start planting crabgrass right off. They wonder why they get that. And it may be that Mars as it is has many benefits. I started working here at NASA Ames as a postdoc with Bob McElroy on controlled ecological life-support systems. There's a lot we can do with martian environments inside before we move out to the environment of Mars and try to mess with it. So I would highly recommend

that not only do we do a thorough job with robotic spacecraft on Mars, but we do a thorough job living inside and trying to figure out what kind of a puzzle Mars presents.

Donna Shirley: Stan, you dealt with this issue in your book with the Reds versus the Greens. What are some of the ethics of making decisions about terraforming Mars?

Kim Stanley Robinson: Ah, the Reds versus the Greens. This is a question in environmental ethics that has been completely obscured by this possibility of life on Mars.

After the Viking mission, and for about a decade or so, up to the findings of the ALH meteorite, where suddenly martian bacteria were postulated again, we thought of Mars as being a dead rock. And yet there were still people who were very offended at the idea of us going there and changing it, even though it was nothing but rock. So this was an interesting kind of limit case in environmental ethics, because this sense of what has standing. People of a certain class had standing, then all the people had standing, then the higher mammals had standing—in each case it's sort of an evolutionary process where, in an ethical sense, more and more parts of life had standing, and need consideration and ethical treatment from us. They aren't just there to be used.

When you get to rock, it seemed to me that there would be very few people (wanting to preserve it). And yet, when I talked about my project, when I was writing it, it was an instinctive thing, that Mars has its own, what environment ethicists would call, "intrinsic worth," even as a rock. It's a pretty interesting position. And I had some sympathy for it, because I like rocky places myself. If somebody proposed irrigating and putting forests in Death Valley, I would think of this as a travesty. I have many favorite rockscapes, and a lot of people do.

So, back and forth between Red and Green, and one of the reasons I think that my book was so long was that it was just possible to imagine both sides of this argument for a very long time. And I never really did reconcile it in my own mind except that it seemed to me that Mars offered the solution itself. If you think of Mars as a dead rock and you think it has intrinsic worth, it should not be changed, then you look at the vertical scale of Mars and you think about terraforming, and there's a 31-kilometer difference between the highest points on Mars and the lowest. I reckoned about 30 percent of the martian surface would stay well above an atmosphere that people could live in, in the lower elevations. So maybe you could have it both ways. I go back and forth on this teeter-totter. But of course now it's a kind of an older teeter-totter because we have a different problem now.

Read the original article at http://www.astrobio.net/news/article1020.html.

DID COMETS FLOOD EARTH’S OCEANS?ESA release

16 June 2004

Did the Earth form with water locked into its rocks, which then gradually leaked out over millions of years? Or did the occasional impacting comet provide the Earth’s oceans? The Ptolemy experiment on Rosetta may just find out.

Did comets provide the water for Earth's oceans? Image credit: Carl Walker.

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The Earth needed a supply of water for its oceans, and the comets are large celestial icebergs—frozen reservoirs of water orbiting the Sun. Did the impact of a number of comets, thousands of millions of years ago, provide the Earth with its supply of water? Finding hard scientific evidence is surprisingly difficult. Ptolemy may just provide the information to understand the source of water on Earth. It is a miniature laboratory designed to analyze the precise types of atoms that make up familiar molecules like water. Atoms can come in slightly different types, known as isotopes. Each isotope behaves almost identically in a chemical sense but has a slightly different weight because of extra neutrons in its nucleus.

Artist's conception of Rosetta and the Philae lander. Image credit: ESA.

Ian Wright is the principal investigator for Ptolemy, an instrument on Rosetta’s Philae lander. By analyzing with Ptolemy the mix of isotopes found in Comet 67P/Churyumov-Gerasimenko, he hopes to say whether comet water is similar to that found in Earth’s oceans. Recent results from the ground-based observation of another comet, called LINEAR, suggested that they probably are the same. If this is true, then scientists have solved another puzzle. However, if the comets are not responsible for Earth’s oceans, then planetary scientists and geophysicists will have to look elsewhere.

For example, the answer could be closer to home, through processes related to vulcanism. Also, meteorites (chunks of asteroids or comets that fall to Earth) have been found to contain water but it is bound to the minerals and in nothing like the quantity found in comets. However, since the Earth formed from rocks similar to the asteroids, it is feasible that enough water could have been supplied that way.

If comets did not supply Earth’s oceans then it implies something amazing about the comets themselves. If Ptolemy finds that they are made of extremely different isotopes, it means that they may not have formed in our Solar System at all. Instead, they could be interstellar rovers captured by the Sun’s gravity.

Rosetta, Philae and Ptolemy will either solve one scientific mystery, or open another whole set of new ones.

Read the original news release at http://www.esa.int/export/esaCP/SEMGX93VQUD_index_0.html.

NEW ADDITIONS TO THE ASTROBIOLOGY INDEXBy David J. Thomashttp://www.lyon.edu/projects/marsbugs/astrobiology/

16 June 2004

Astrobiology and planetary engineering articleshttp://www.lyon.edu/projects/marsbugs/astrobiology/online_articles1.html

Astrobiology Magazine, 2004. Great terraforming debate, part I: giving Mars back its heartbeat. Astrobiology Magazine.

Astrobiology Magazine, 2004. Great terraforming debate, part II: looking for martian life. Astrobiology Magazine.

Astrobiology Magazine, 2004. Great terraforming debate, part III: should we terraform? Astrobiology Magazine.

Human space flight articleshttp://www.lyon.edu/projects/marsbugs/astrobiology/online_articles3.html

B. Berger, 2004. Moon-to-Mars Commission recommends major changes at NASA. Space.com.

SETI articleshttp://www.lyon.edu/projects/marsbugs/astrobiology/online_articles4.html

Science Magazine, 2004. Dr. Doolittle in the doghouse. Astrobiology Magazine.

CASSINI UPDATESNASA/JPL releases

Cassini Significant EventsNASA/JPL release, 3-9 June 2004

The most recent spacecraft telemetry was acquired from the Goldstone tracking station on Wednesday, June 9. The Cassini spacecraft is in an excellent state of health and is operating normally. Information on the present position and speed of the Cassini spacecraft may be found on the "Present Position" web page located at http://saturn.jpl.nasa.gov/operations/present-position.cfm.

On-board instrument activities this week included continuation of Ultraviolet Imaging Spectrograph (UVIS) mapping of the Saturn magnetosphere in neutral and ion photon emissions. The purpose of this activity is to derive the distribution and density of atomic and molecular species. The suite of Magnetospheric and Plasma Science (MAPS) instruments continued its survey of Saturn's magnetosphere, in particular looking for upstream solar wind conditions and wave phenomena as we approach Saturn's bow shock. The Imaging Science Subsystem (ISS) continued data collection for a Titan movie that documents evidence of cloud motion that will be used to measure winds. Additional instrument activities included a Radio and Plasma Wave Science High Frequency Receiver Calibration, a Cassini Plasma Spectrometer Power-On-Reset mini-sequence, periodic instrument maintenance of the Radio Science Subsystem, and Visual and Infrared Mapping Spectrometer (VIMS) instrument expanded block #3 SSR load, cleanup, verification, and memory read out.

Spacecraft activities included power cycling of Reaction Wheel Assembly (RWA)-1, uplink and execution of an RWA bias for Phoebe, and an ACS post Trajectory Correction Maneuver (TCM)-20 mass properties parameter update. In support of the upcoming Phoebe flyby, the first "Live Update" process was executed and the output products uplinked to the spacecraft.

While the knowledge of the spacecraft trajectory and the various bodies in the Saturnian system are known well enough in advance that science activities can be planned, in some cases the detailed position knowledge isn't known well enough to ensure that the goals of the science teams are met. In these cases,

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the Live Update process is used. For this process the desired activity design is loaded to the spacecraft with "default" timing and pointing data to ensure basic science return. Then, just before the encounter the most recent Navigation knowledge is used to update that default timing and pointing to maximize the science return. The Live Update process is especially needed with the Phoebe flyby. This target is so small and faint when viewed from the ground that the only targeting data available is from Cassini as it approaches closer and closer. This data provides the navigation team sufficient insight to make accurate trajectory predictions that meet the science needs.

Closing in on the Phoebe flyby, members of the Cassini Navigation team worked every day after TCM-20 to collect, reduce, and analyze spacecraft and Phoebe position data, and to evaluate the remaining position uncertainty against the pointing knowledge requirements. On Sunday, June 6th, the team was confident that they had good enough data to commence with the update process, and the updated trajectory files were released to the project. The science teams then took those files and assessed the impact to their activities if the update were to be executed or not. Agreement was reached at the Live Update Go/No Go meeting that the update was both warranted and the Navigation knowledge was sufficient to meet the science intent. A "go" was then given for a continuation of the process and the Sequence Team executed the update.

There is no DSN track on Friday June 11 when the Phoebe encounter actually occurs. The flight team is eager with anticipation for the results of the flyby that will be downlinked over the Madrid and Goldstone DSN complexes on Saturday June 12.

A NASA News Release, 2004-145 June 9, 2004, entitled "Cassini Spacecraft near First Stop in Historic Saturn Tour" giving more information on the flyby itself can be found at http://www.nasa.gov/cassini. In addition, Aviation Week & Space Technology, June 7, 2004 has published an article on Phoebe and the TCMs that are getting us there.

Background sequence products were released as part of the Preliminary Sequence Integration and Validation (PSIV) 2 cycle for tour sequence S02, and a final SIV sequence change request and waiver approval meeting was held. Preliminary port#2 for Science Operations Plan Implementation of tour sequences S29 and S30 occurred this week along with preliminary port #1 for S31 and S32. The products have been merged, checked and any problems reported to the teams. As part of the Science Planning aftermarket process, all requested changes to the S06 sequence were delivered this week. An assessment meeting will be held on June 14.

In the last week, 500 ISS images were obtained and were distributed along with 875 VIMS cubes. The total number of ISS images acquired since the start of Approach Science is now 10219, and the number of VIMS cubes is 3217.

As reported at the last Cassini Project Science Group meeting, the Cosmic Dust Analyzer (CDA) instrument has discovered dust storms from Saturn! The detected particles are tiny and fast, similar to the dust stream particles from Jupiter. They appear not only directly from Saturn, but can be detected as far as 100 degrees off from the direct Saturn-CDA direction.

NASA and European Space Agency (ESA) officials held an arrival press conference for the Cassini-Huygens Saturn mission this week. The press conference originated out of NASA Headquarters where panelists discussed an overview of the Saturn tour, Huygens Probe mission, the Phoebe flyby, and the challenging maneuver to place the spacecraft in orbit around Saturn. Panelists included: Dr. Ed Weiler, NASA's Associate Administrator for Space Science,

Washington, DC. Orlando Figueroa, Director, Solar System Exploration Division, NASA

Headquarters. Dr. Charles Elachi, Director, NASA JPL, Team Leader for the Cassini

Radar Instrument, Pasadena, CA. Robert Mitchell, JPL Cassini Program Manager. Dr. Jean-Pierre Lebreton, ESA Huygens Probe Project Manager.

The Cassini arrival press kit is available to download from the Cassini web site at http://saturn.jpl.nasa.gov/news/press-kits/cassini-arrival.pdf. In conjunction with the press briefing, the Imaging Team released two new images. One shows a colorful Saturn looming up ahead. The other indicates the radial position of Cassini's ring plane crossing relative to the main rings

and some of Saturn's moons. The images can be found at http://saturn.jpl.nasa.gov.

From the other side of the globe, the Imperial College of Science, Technology and Medicine, London, where members of the Magnetometer Subsystem (MAG) instrument team reside have issued a press release on upcoming Cassini activities. MAG maps the internal magnetic field of the planet, and will give a better idea of what the interior of the planet is like, how the magnetic field is formed, how it is still being generated, and some further clues about how the solar system was formed. For more information please link to: http://www.imperial.ac.uk/p5294.htm

The University of Arizona is hosting a Cassini event on June 19. For maps, directions, and more information link to http://www.lpl.arizona.edu/pop/.

Outreach participated in "Scout Expo", an event for Boy Scouts and Cub Scouts from the San Gabriel Valley Council of the Boy Scouts Association of America. Over 2,000 scouts attended the one-day event. Cassini staff members spoke about the flight project, the upcoming Saturn tour, and assisted in helping 'Bear Scouts' complete elective merits in space exploration. The Cassini Mission to Saturn and Cub Scout pack 482 from Glendora, California hosted the booth. Scout Expo took place at Santa Anita Race Track in Arcadia, California.

Cassini Spacecraft near First Stop in Historic Saturn TourNASA/JPL release 2004-145, 9 June 2004

The most complex interplanetary mission ever launched is about to meet one of the solar system's enigmatic moons. Cassini will fly by Saturn's largest outer moon, Phoebe, on Friday, June 11. The closest approach is at approximately 1:56 PM Pacific Time, just 19 days before Saturn arrival. A final trajectory correction maneuver is scheduled for June 16. On arrival date, June 30, Cassini will become the first spacecraft to orbit Saturn. Once in orbit it will conduct an extensive, four- year tour of the Saturn system, including its majestic rings and many known moons.

The three images shown here, the latest of which is twice as good as any image returned by the Voyager 2 spacecraft in 1981, were captured in the past week on approach to this outer moon of Saturn. Phoebe's surface is already showing a great deal of contrast, most likely indicative of topography, such as tall sunlit peaks and deep shadowy craters, as well as genuine variation in the reflectivity of its surface materials. Left to right, the three views were captured at a phase (Sun-Saturn-spacecraft) angle of 87 degrees between June 4 and June 7, from distances ranging from 4.1 million kilometers (2.6 million miles) to 2.5 million kilometers (1.5 million miles). The image scale ranges from 25 to 15 kilometers per pixel.

"The arrival date and trajectory to Saturn were specifically selected to accommodate this flyby, which will be the only opportunity during the mission to study Phoebe at close range," said Dave Seal, mission planner for the Cassini-Huygens mission at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Phoebe's orbit is simply too far from Saturn, at almost 13 million kilometers (about 8 million miles), nearly four times as far as the next closest major satellite, Iapetus. A later encounter is not feasible."

"The last time we had observations of Phoebe was by Voyager in 1981," said Dr. Torrence Johnson, former Voyager imaging team member, Galileo project scientist and current Cassini imaging team member. "This time around, the pictures of the mysterious moon will be about 1,000 times better, as Cassini will be closer." Voyager 2 captured images of Phoebe from about 2.2 million kilometers (about 1.4 million miles) away. Cassini will obtain images from a mere 2,000 kilometers (about 1,240 miles) above the moon's surface.

Cassini will also collect spectroscopic and radar data that could decipher the composition and origin of this distant moon. Cassini's Phoebe images, already twice as good as any image returned by Voyager 2, show large craters and variation in surface brightness.

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"We anticipate that Phoebe will be heavily cratered in the higher resolution images we expect to see in the next few days," said Dr. Peter Thomas, a member of the imaging team and a senior research associate at Cornell University, Ithaca, NY, who specializes in studies of small satellites. "The hints of different brightnesses also suggest that the highest resolution images, several hundred times better, will show a variety of materials.

Discovered in 1898 by American astronomer William Henry Pickering, Phoebe is of great interest to scientists. "With the instruments Cassini carries, we might learn more about Phoebe's internal structure and composition. What we have are many unanswered questions. Did it ever melt? Does it have evidence of past interior melting? Was it ever an icy body? Why is Phoebe in such an odd orbit?" said Dr. Dennis Matson, project scientist for the Cassini-Huygens mission at JPL.

Phoebe has a diameter of 220 kilometers (about 136.7 miles), which is equal to about one-fifteenth the diameter of Earth's moon. Phoebe rotates on its axis every nine hours and 16 minutes, and it completes a full orbit around Saturn in about 18 months. Its elliptical orbit is inclined approximately 30 degrees to Saturn's equator. Phoebe's retrograde orbit means that it goes around Saturn in the opposite direction of the larger interior Saturnian moons. Previous ground-based observations have shown water ice present on its surface.

Phoebe is also unusual in that it is very dark. It reflects only six percent of the sunlight it receives. Phoebe's darkness and retrograde orbit suggest that it is most likely a captured object. A captured object is a celestial body that is caught by the gravitational pull of a much bigger body, generally a planet. Some scientists believe Phoebe might even be an object from the outer solar system, similar to the objects found in the Kuiper Belt. The Kuiper Belt is a collection of small icy bodies beyond Pluto that were never drawn together by gravity to form a planet.

"The dark and odd-shaped Phoebe may be a piece of the building blocks from which some of the planets formed," said Dr. Bonnie Buratti, scientist on the Cassini-Huygens mission at JPL. "It might hold clues about the early formation of our solar system."

Cassini Makes Close Observations of PhoebeNASA/JPL release 2004-146, 12 June 2004

With its flyby of Phoebe, the Cassini spacecraft has completed the first satellite flyby in its four-year tour of the Saturn system. NASA's Deep Space Network received confirmation at 7:52 AM PDT today. The spacecraft is operating normally and is in excellent health.

"One down, 52 to go," said Jeremy Jones, chief navigator for the Cassini-Huygens mission at NASA's Jet Propulsion Laboratory, Pasadena, CA. During Cassini's planned four-year tour it will orbit Saturn 76 times and execute 52 close encounters with seven of Saturn's 31 known moons.

"Although this is the first flyby in the Saturn tour, it is the only opportunity to see Phoebe," said Dr. Dennis Matson, project scientist for the Cassini-Huygens mission. "This flyby is key to knowing more about the mysterious odd-ball, which has been the object of interest of many scientists."

Cassini came within approximately 2,068 kilometers (about 1,285 miles) of the dark moon on Friday, June 11. The spacecraft was pointing its instruments at the moon during the flyby. Several hours later it turned to point its antenna to Earth. The signal was received through the Deep Space Network antennas in Madrid, Spain and Goldstone, in California's Mojave Desert. It was traveling at a relative speed of 20,900 kilometers per hour (13,000 miles per hour) relative to Saturn. It's been 23 years since we last visited Phoebe. The Voyager 2 flyby in 1981 was from 2.2 million kilometers, (about 1.4 million miles), 1,000 times further away.

When it was discovered in 1898, Phoebe was Saturn's outermost known moon. That changed with the discovery of several smaller moons in 2000. Phoebe is almost four times farther from Saturn than its nearest major neighbor, Iapetus, and substantially larger than any of the other moons orbiting at comparable distances. With a diameter of 220 kilometers (about 140 miles), it rotates on its axis every nine hours and 16 minutes and it completes a full orbit around Saturn in about 18 months. All of Saturn's moons except for Phoebe and Iapetus orbit very nearly in the plane of Saturn's

equator. Phoebe's orbit is highly eccentric and retrograde; it orbits backwards with respect to the direction of the other moons.

Based on data from the Voyager flyby, Phoebe resembles a sort of dark asteroid. It may be very primitive. "All previous indications suggest that it may be a captured Kuiper Belt object, one of the millions of asteroid-like bodies from outside the orbit of Pluto," said Dr. Bonnie Buratti, scientist on the Cassini-Huygens mission at JPL. "With the flyby behind us, we may soon know whether Phoebe's composition is unmodified since the time it was formed in the outer solar system. If it turns out to be a Kuiper Belt object, we could be looking at the most detailed close-ups of any such object ever taken."

First pictures after the flyby are expected later today. After the Phoebe flyby, Cassini is on course for Saturn. A last trajectory correction maneuver is scheduled for June 16. Cassini will fire its engine for 96-minutes before going into orbit around Saturn on June 30 in U.S. time zones (July 1 Universal Time).

Cassini's Flyby of Phoebe Shows a Moon with a Battered PastNASA/JPL release 2004-147, 12 June 2004

First images from the Cassini flyby of Phoebe reveal it to be a scarred, cratered outpost with a very old surface and a mysterious past, and a great deal of variation in surface brightness across its surface.

In the first image (at left) in which Phoebe looks somewhat like a sideways skull, the large crater near the bottom displays a complex and rugged interior. The lower right hand part of Phoebe appears to be covered by bright wispy material. The second, higher resolution image further reveals the moon's battered surface, including a crater near the right hand edge with bright rays that extend outward from its center. This suggests that dark material coats the outside. Features reminiscent of those seen on the Martian moon Phobos—such as linear grooves—are faintly visible in the upper part of this image. There are suggestions of linear ridges or grooves and of chains of craters, perhaps radial to a large crater just hidden on the un-illuminated region in the upper left. Left to right, the two views were obtained at phase, or Sun-Phoebe-spacecraft, angles of approximately 86 degrees, and from distances ranging from 143,068 kilometers (88,918 miles) to 77,441 kilometers (48, 130 miles); for reference, Cassini's closest approach to Phoebe was approximately 2,068 kilometers (1,285 miles). The image scale ranges from 0.86 to 0.46 kilometers (0.53 to 0.29 miles) per pixel. No enhancement of any kind has been performed on the images.

"What spectacular images," said Dr. Carolyn Porco, Cassini Imaging Team leader at the Space Science Institute in Boulder, CO. "So sharp and clear and showing a great many geological features, large and small. It's obvious a lot of new insights into the origin of this strange body will come as a result of all this."

"What we are seeing is very neat. Phoebe is a heavily cratered body. We might be seeing one of the chunks from the formation of the solar system, 4.5 billion years ago. It's too soon to say," said Dr. Torrence Johnson, Cassini imaging team member at NASA's Jet Propulsion Laboratory, Pasadena, CA. "It's important to see the big picture from all of the other instruments to get the global view on this tiny moon."

Dr. Gerhard Neukum, an imaging team member from Freie University in Berlin, said, "It is very interesting and quite clear that a lot of craters smaller than a kilometer are visible. This means, besides the big-ones, lots of projectiles smaller than 100 meters (328 feet) have hit Phoebe." Whether these projectiles came from outside or within the Saturn system is debatable.

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There is a suspicion that Phoebe, the largest of Saturn's outer moons, might be parent to the other, much smaller retrograde outer moons that orbit Saturn.

This eye-popping high-resolution image of Phoebe's pitted surface taken very near closest approach shows a 13-kilometer (8-mile) diameter crater with a debris-covered floor. Part of another crater of similar size is visible at left, as is part of a larger crater at top and many scattered smaller craters. The radial streaks in the crater are due to down slope movements of loose fragments from impact ejecta. Also seen are boulders ranging from about 50 to 300 meters (160 to 990 feet) in diameter. The building-sized rocks may have been excavated by large impacts, perhaps from some other region of Phoebe rather than the craters seen here. There is no visible evidence for layering of ice and dark material or a hardened crust in this region, as on other parts of this moon. Some of the relatively bright spots are from small impacts that excavated bright material from beneath the dark surface. Images like this provide information about impact processes on Phoebe. This image was obtained at a phase, or Sun-Phoebe-spacecraft, angle of 78 degrees, and from a distance of 11,918 kilometers (7,407 miles). The image scale is approximately 18.5 meters (60.5 feet) per pixel. The illumination is from the right. No enhancement was performed on this image.

Dr. Joseph Burns, an imaging team member and professor at Cornell University, Ithaca, NY, said, "Looking at those big 50 kilometers (31 mile) craters, one has to wonder whether their impact ejecta might be the other tiny moons that orbit Saturn on paths much like Phoebe's."

All planned 11 instruments operated as expected and all data was acquired. Scientists plan to use the data to create global maps of the cratered moon, and to determine Phoebe’s composition, mass and density. It will take scientists several days to pour over the data to make more concrete conclusions.

Cassini came within approximately 2,068 kilometers (about 1,285 miles) of the dark moon on Friday, June 11. The spacecraft was pointing its instruments at the moon during the flyby. Several hours later it turned to point its antenna to Earth. The signal was received through the Deep Space Network antennas in Madrid, Spain and Goldstone, in California’s Mojave Desert, at 7:52 AM PDT today. Cassini was traveling at a relative speed of 20,900 kilometers per hour (13,000 miles per hour) relative to Saturn. It’s been 23 years since a spacecraft last visited Phoebe. The Voyager 2 flyby in 1981 was at a distance from 2.2 million kilometers, (about 1.4 million miles), 1,000 times farther away.

With the Phoebe accomplished, Cassini is on course for Saturn. A trajectory correction maneuver is scheduled for June 16. Cassini will conduct a critical 96-minute burn before going into orbit around Saturn on June 30 (July 1 Universal Time). During Cassini's planned four-year tour it will conduct 76 orbits around the Saturn system and execute 52 close encounters with seven of Saturn’s 31 known moons.

Phoebe's Surface Reveals Clues to its Origin NASA/JPL release 2004-149, 14 June 2004

Images collected during Cassini's close flyby of Saturn's moon, Phoebe, have yielded strong evidence that the tiny object may contain ice-rich material, overlain with a thin layer of darker material perhaps 300 to 500 meters (980 to 1,600 feet) thick. The surface of Phoebe is also heavily potholed with large and small craters. Images reveal bright streaks in the ramparts of the largest craters, bright rays which emanate from smaller craters, and uninterrupted grooves across the face of the body.

Images like this one, showing bright wispy streaks thought to be ice revealed by subsidence of crater walls, are leading to the view that Phoebe is an ice-rich body overlain with a thin layer of dark material. Obvious down slope motion of material occurring along the walls of the major craters in this image is the cause for the bright streaks, which are over-exposed here. Significant slumping has occurred along the crater wall at top left.

"The imaging team is in hot debate at the moment on the interpretations of our findings," said Dr. Carolyn Porco, Cassini imaging team leader at the Space Science Institute in Boulder, CO. "Based on our images, some of us are leaning towards the view that has been promoted recently, that Phoebe is probably ice-rich and may be an object originating in the outer solar system, more related to comets and Kuiper Belt objects than to asteroids."

In ascertaining Phoebe's origin, imaging scientists are noting important differences between the surface of Phoebe and that of rocky asteroids which have been seen at comparable resolution. "Asteroids seen up close, like Ida, Mathilde, and Eros, and the small martian satellites do not have the bright 'speckling' associated with the small craters that are seen on Phoebe," said Dr. Peter Thomas, an imaging team member from Cornell University, Ithaca, NY.

The landforms observed in the highest resolution images also contain clues to the internal structure of Phoebe. Dr. Alfred McEwen, an imaging team member from the University of Arizona, Tucson, said, "Phoebe is a world of dramatic landforms, with craters everywhere, landslides, and linear structures such as grooves, ridges, and chains of pits. These are clues to the internal properties of Phoebe, which we'll be looking at very closely in order to understand Phoebe's origin and evolution."

"I think these images are showing us an ancient remnant of the bodies that formed over four billion years ago in the outer reaches of the solar system," said Dr. Torrence Johnson, an imaging team member from NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Battered and beat-up as it is, it is still giving us clues to its origin and history."

Phoebe may be an icy interloper from the distant outer solar system which found itself captured by giant Saturn in its earliest, formative years.

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Final conclusions on Phoebe's origins await a combination of the results on Phoebe's surface structures, mass and composition gathered from all 11 instruments, which collected data during the flyby on June 11, 2004.

"This has been an impressive whirlwind flyby and it's only a curtain raiser on the events about to begin," said Porco.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA's Office of Space Science, Washington, DC. JPL designed, developed and assembled the Cassini orbiter.

For the latest images and more information about the Cassini- Huygens mission on the Internet, visit http://www.nasa.gov/cassini. For information about NASA and agency programs on the Internet, visit http://www.nasa.gov. Contacts:Carolina Martinez Jet Propulsion Laboratory, Pasadena, CAPhone: 818-354-9382

Dwayne Brown NASA Headquarters, Washington, DCPhone: 202-358-1726

Heidi FinnCassini Imaging Central Laboratory for OperationsSpace Science Institute, Boulder, COPhone: 720-974-5859

Additional articles on this subject are available at:http://www.astrobio.net/news/article1012.htmlhttp://www.astrobio.net/news/article1014.htmlhttp://www.esa.int/esaCP/SEMNL63VQUD_index_0.htmlhttp://www.space.com/scienceastronomy/cassini_phoebe_040610.htmlhttp://www.space.com/imageoftheday/image_of_day_040611.htmlhttp://www.space.com/scienceastronomy/cassini_flew_by_040612.htmlhttp://www.space.com/scienceastronomy/phoebe_unveiled_040615.htmlhttp://www.spacedaily.com/news/cassini-04p.htmlhttp://www.spacedaily.com/news/cassini-04q.htmlhttp://www.spacedaily.com/news/cassini-04u.htmlhttp://www.spacedaily.com/news/cassini-04w.htmlhttp://www.spacedaily.com/news/cassini-04x.htmlhttp://www.spacedaily.com/2004/040614210621.is7dw1pc.htmlhttp://spaceflightnow.com/cassini/040609phoebe.htmlhttp://spaceflightnow.com/cassini/040611phoebe.htmlhttp://spaceflightnow.com/cassini/040611storms.htmlhttp://spaceflightnow.com/cassini/040612phoebeflyby.htmlhttp://spaceflightnow.com/cassini/040612phoebeclose.htmlhttp://spaceflightnow.com/cassini/040612preview.htmlhttp://spaceflightnow.com/cassini/040612science.htmlhttp://spaceflightnow.com/cassini/040612hurdles.htmlhttp://spaceflightnow.com/cassini/040612soi.htmlhttp://spaceflightnow.com/cassini/040613phoebe.htmlhttp://spaceflightnow.com/cassini/040614phoebe.htmlhttp://spaceflightnow.com/cassini/040615swirl.htmlhttp://www.universetoday.com/am/publish/phoebe_cassini_first_target.htmlhttp://www.universetoday.com/am/publish/even_closer_phoebe.htmlhttp://www.universetoday.com/am/publish/close_up_phoebe_crater.htmlhttp://www.universetoday.com/am/publish/cassini_makes_phoebe_flyby.htmlhttp://www.universetoday.com/am/publish/cassini_passes_phoebe.html

MARS ROVERS GOING THE EXTRA MILENASA/JPL release 2004-151

15 June 2004

NASA's Mars rovers are delighting scientists with their extra credit assignments. Both rovers successfully completed their primary three-month missions in April. The Spirit rover is exploring a range of martian hills that took two months to reach. It is finding curiously eroded rocks that may be new pieces to the puzzle of the region's past. Spirit's twin, Opportunity, is also negotiating sloped ground. It is examining exposed rock layers inside a crater informally named "Endurance."

This false-color image taken by the panoramic camera on the Mars Exploration Rover Spirit shows the rock dubbed "Pot of Gold" (upper left), located near the base of the "Columbia Hills" in Gusev Crater. Scientists are intrigued by this unusual-looking, nodule-covered rock and plan to investigate its detailed chemistry in coming sols. This picture was taken on sol 159 (June 14, 2004). To the right is a set of rocks referred to as "Rotten Rocks" for their resemblance to rotting loaves of bread. The insides of these rocks appear to have been eroded, while their outer rinds remain more intact. These outer rinds are reminiscent of those found on rocks at Meridiani Planum's "Eagle Crater." This image was captured on sol 158 (June 13, 2004). Image credit: NASA/JPL/Cornell.

"Both rovers have begun exploring brand new places," said Dr. Mark Adler, mission manager at NASA's Jet Propulsion Laboratory, Pasadena, CA. "Opportunity has entered Endurance Crater. Spirit has arrived at the Columbia Hills. Both rovers are getting their second wind in bonus time, and we are very excited about the scientific potential we see at their new homes. Of course, the terrain at both locations is challenging, one up and one down. We are making certain that we proceed safely to keep these wonderful machines as healthy as we can for as long as we can."

Spirit began climbing into Columbia Hills late last week, and right away sent pictures of tantalizing rocks. "Some of the rocks appear to be disintegrating. They have an odd kind of rotting appearance, with soft interiors and resistant rinds or hulls," said Dr. Larry Soderblom, a rover science-team member from the U.S. Geological Survey, Flagstaff, AZ. "The strangest things we've encountered are what we're calling hooded cobras, which are evidently the resistant remnants of some of those rocky rinds. They stand above the surface like small canopies." Another rock, dubbed "Pot of Gold," appears to have nodules and resistant planes in a softer matrix. Scientists have chosen it as a target for Spirit to examine with the instruments on the rover's robotic arm. Afterwards, controllers plan to send Spirit to an outcrop farther uphill.

"Although it's too early to even speculate as to the processes these rocks have recorded, we are tremendously excited over the new prospects," Soderblom said. The Columbia Hills rise approximately 90 meters (about 300 feet) above a plain Spirit crossed to reach them. Scientists anticipate a complex blend of rocks in the hills, perhaps holding evidence about a broader range of environmental conditions than has been seen in the volcanic rubble surfacing the plain. The entire area Spirit is exploring is within Gusev Crater. Orbital images suggest water may have once flowed into this Connecticut-sized basin. "Halfway around Mars, Opportunity has driven about five meters (16 feet) into stadium-sized Endurance Crater. As we look back up toward the rim, we can see the progress we've made," said Scott McLennan, science-team member from the State University of New York, Stony Brook. Opportunity's first target inside the crater is a flat-lying stone about 36 centimeters by 15 centimeters (14 inches by 6 inches) dubbed "Tennessee" for its shape. Opportunity will inspect it for analysis with the spectrometers and microscopic imager on the rover's robotic arm. It is in a layer geologists believe corresponds to sulfate-rich rocks. The rocks are similar to those, in which Opportunity previously found evidence for a body of water covering the ground long ago. "The next step will be to move farther down from this layer to our first close-up look at a different sedimentary sequence," McLennan said. "Color differences suggest at least three lower, older layers are exposed below Opportunity's location."

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This false-color image shows the area within "Endurance Crater," currently being investigated by the Mars Exploration Rover Opportunity. The rover is inspecting a hole it drilled into a flat rock (center) dubbed "Tennessee," which scientists believe may be made up of the same evaporite-rich materials as those found in "Eagle Crater." The overall geography inside Endurance is more complex than scientists anticipated, with at least three distinct bands of rock visible in front of the rover. Scientists hope to investigate the second and third layers of rock for more clues to Mars' history. This image was taken on sol 133 (June 8, 2004) with the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters. Image credit: NASA/JPL/Cornell.

"The interpretation of those lower units is in a state of flux," he said. "At first, we thought we would encounter poorly consolidated, sandy material. But as we get closer, we're seeing more-consolidated, harder rock deeper into the crater. If we can get to the lower units, this will be the first detailed stratigraphic section ever done on another planet. We're doing exactly what a field geologist would be doing." Spirit is showing what may be the first sign of age and wear. "The right front wheel is drawing about two to three times as much current as the other wheels, and that may be a symptom of degradation," Adler said. "There may be steps we can take to improve it. We'll be studying that possibility during the next few weeks."

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Office of Space Science, Washington, DC. Images and additional information about the project are available from JPL at http://marsrovers.jpl.nasa.gov and from Cornell University, Ithaca, NY, at http://athena.cornell.edu.

Contacts:Dwayne BrownNASA Headquarters, Washington, DCPhone: 202-358-1726

Guy WebsterJet Propulsion Laboratory, Pasadena, CAPhone: 818-354-6278

Additional articles on this subject are available at:http://www.astrobio.net/news/article1019.htmlhttp://www.cnn.com/2004/TECH/space/06/09/endurance.crater.plunge/index.htmlhttp://www.space.com/missionlaunches/opportunity_rim_040611.htmlhttp://spaceflightnow.com/mars/mera/040608status.htmlhttp://www.space.com/missionlaunches/rovers_update_040608.htmlhttp://www.space.com/missionlaunches/rovers_winter_040608.htmlhttp://www.space.com/missionlaunches/rovers_update_040613.htmlhttp://spaceflightnow.com/mars/mera/040609drive.htmlhttp://spaceflightnow.com/mars/mera/040615spiritwheel.htmlhttp://www.universetoday.com/am/publish/opportunity_checks_edge_crater.htmlhttp://www.universetoday.com/am/publish/spirit_reaches_columbia_hills.html

MARS EXPRESS: EVIDENCE OF FLOODING AT MANGALA VALLESESA release

9 June 2004

These images of fluvial surface features at Mangala Valles on Mars were obtained by the High Resolution Stereo Camera (HRSC) on board the ESA Mars Express spacecraft. The HRSC has imaged structures several times which are related to fluvial events in the past on Mars. The region seen here is situated on the south-western Tharsis bulge and shows the mouth of the Mangala Valles and Minio Vallis outflow channels. The source of the outflow channel is related to the Mangala Fossa, a fissure running east-west for several hundred kilometers.

Color image of Mangala Valles.

One theory about its formation is related to a process known on Earth as "dyke emplacement". This is when hot molten rock finds its way to the surface through a fissure, releasing large amounts of water by the melting of subsurface ice. It is still unclear for how long and to what extent water, mud or even ice masses and wind have carved the channel here. This theory on its formation has several analogs on Earth. Events like the one proposed for Mangala Valles occur on Earth, for example in Iceland, where volcanic activity causes episodic releases of water from subsurface reservoirs, causing catastrophic floods.

Along the channel troughs, areas with so-called "chaotic terrain" features favor the idea of the existence of subsurface ice. The small-scale chaotic terrain is characterized by isolated blocks of surface material which have been randomly arranged during the release of subsurface water and subsequent collapse of the surface. Huge areas of chaotic terrain can be found near the source areas of the outflow channels around Chryse Planitia, such as Kasei, Maja and Ares Valles.

Perspective view of Mangala Valles.

Beside the large outflow channels, a variety of smaller "dendritic" valley networks with a number of tributary valleys can be seen near the main channels. This indicates possible precipitation.

The images were taken during orbit 299 with a resolution of 28 meters per pixel. The image center is located at 209° E longitude and 5° S latitude. For practical use on the internet, the images have been reduced in resolution. The red/cyan 3D anaglyph image was created using the stereo- and nadir channels of the HRSC. The perspective view was calculated from the digital terrain model derived from the stereo and color information of the image data. The

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3D images require stereoscopic glasses to view. For more information on Mars Express HRSC images, you might like to read our updated "Frequently Asked Questions" (http://www.esa.int/export/SPECIALS/Mars_Express/SEMJBQXLDMD_0.html).

Read the original news release at http://www.esa.int/SPECIALS/Mars_Express/SEM4SS2VQUD_2.html.

Additional articles on this subject are available at:http://spaceflightnow.com/mars/marsexpress/040609marsexpress.htmlhttp://www.universetoday.com/am/publish/wallpaper_flood_plains_mars.html

MARS GLOBAL SURVEYOR IMAGESNASA/JPL/MSSS release

3-9 June 2004

The following new images taken by the Mars Orbiter Camera (MOC) on the Mars Global Surveyor spacecraft are now available.

Features in Granicus Valles (Released 03 June 2004)http://www.msss.com/mars_images/moc/2004/06/03/index.html

Layered Slopes (Released 04 June 2004)http://www.msss.com/mars_images/moc/2004/06/04/index.html

Streaks and Lava Flows (Released 05 June 2004)http://www.msss.com/mars_images/moc/2004/06/05/index.html

Cracks and Lines (Released 06 June 2004)http://www.msss.com/mars_images/moc/2004/06/06/index.html

June 2004 Autumn Dunes (Released 07 June 2004)http://www.msss.com/mars_images/moc/2004/06/07/index.html

Crater Wall with Gullies (Released 08 June 2004)http://www.msss.com/mars_images/moc/2004/06/08/index.html

Bright Dust Devil Tracks (Released 09 June 2004)http://www.msss.com/mars_images/moc/2004/06/09/index.html

All of the Mars Global Surveyor images are archived at http://www.msss.com/mars_images/moc/index.html.

Mars Global Surveyor was launched in November 1996 and has been in Mars orbit since September 1997. It began its primary mapping mission on March 8, 1999. Mars Global Surveyor is the first mission in a long-term program of Mars exploration known as the Mars Surveyor Program that is managed by JPL for NASA's Office of Space Science, Washington, DC. Malin Space Science Systems (MSSS) and the California Institute of Technology built the MOC using spare hardware from the Mars Observer mission. MSSS operates the camera from its facilities in San Diego, CA. The Jet Propulsion Laboratory's Mars Surveyor Operations Project operates the Mars Global Surveyor spacecraft with its industrial partner, Lockheed Martin Astronautics, from facilities in Pasadena, CA and Denver, CO.

MARS ODYSSEY THEMIS IMAGESNASA/JPL/ASU release

7-11 June 2004

Hebes Mensa (Released 7 June 2004)http://themis.la.asu.edu/zoom-20040607a.html Thaumasia Planium (Released 8 June 2004)http://themis.la.asu.edu/zoom-20040608a.html

Nili Fossae (Released 9 June 2004)http://themis.la.asu.edu/zoom-20040609a.html

Hebes Mensa (Released 10 June 2004)http://themis.la.asu.edu/zoom-20040610a.html

Day And Night In Terra Meridiani (Released 11 June 2004)http://themis.la.asu.edu/zoom-20040611a.html

All of the THEMIS images are archived at http://themis.la.asu.edu/latest.html.

NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, DC. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

ROSETTA: CRUISE PHASE BEGINSESA release

14 June 2004

The first part of the Rosetta Commissioning Phase was successfully completed in the reporting period. The Cruise 1 Phase formally started on 7 June 2004 and will last until the start of the second and last commissioning slot in September/October 2004. The last payload activities in this phase, the repetition of OSIRIS measurements (slot2b), were successfully completed.

On the subsystems side the first battery was reconditioned by discharging it to a lower level of charge, to be kept for the entire Cruise 1. Some new On-Board Control Procedures (OBCPs), developed post-launch by the ESOC Flight Control Team to support on-board software maintenance activities, were uplinked to the spacecraft. They will be first used in the next reporting period to ease Star Tracker and Camera software patching activities.

The spacecraft was slewed to bring the Sun to +50° above the +X axis for 24 hours (8 June), then up to +70° on 9 June, to characterize the thermal effects of high solar aspect angles at short Sun distances (currently still below 0.9 AU). During this activity, an S-band carrier without modulation was switched on via MGA / TRSP2 and successfully acquired at New Norcia in coherent mode. Finally, reconditioning of the second battery started on the 10 June.

For the second time a ground station pass over New Norcia was skipped. At the end of the last New Norcia pass in the reporting period (DOY 163, 01:40) Rosetta was at 49 million km from the Earth. The one-way signal travel time was 2 minutes 44 seconds.

Read the original news release at http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=35311.

End Marsbugs, Volume 11, Number 25.

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